1. Field of the Invention
The present invention relates to a novel diaryl butyric acid derivative and the pharmaceutically acceptable salt thereof as well as a production process thereof. More specifically, it relates to a diaryl butyric acid derivative or the pharmaceutically acceptable salt thereof which is effective for ameliorating and curing (or treating) various symptoms based on cerebral organic disorders (or cerebral dysfunction or brain (organic) syndrome) and pathergasia.
The term "cerebral organic disorders" used herein means various symptoms derived from cerebral ischemic disorders or diseases such as cerebral infarct sequela, cerebral hemorrhage sequela, and cerebral arteriosclerosis sequela and various organic disorders derived from senile dementia, dementia presenilis, amnesia, cephalic traumatic sequela, and cerebral operation sequela. Furthermore, the term "pathergasia" used herein means psychogender organic diseases like mania, melancholia, neurosis, Parkinson's disease, schizophrenia, schizophrenia-like disorders, and chorea (or Huntington's chorea) as well as various syndromes derived from medicines and alcoholic beverages.
2. Description of the Related Art
Cerebral cells retain their own intracellular environments which are completely different from the surrounding environments, i.e., extracellular fluids, and while this difference is maintained, cerebral cells are alive. For this reason, it is necessary for energy to be always generated and supplied to cerebral cells. Most of the energy required by cerebral nerve cells is supplied by oxygen and glucose. These energy sources are not substantially stored in the brain and, therefore, are always to be supplied from the blood.
If certain cerebral disturbances or disorders occur, and if the supply of oxygen and glucose to the brain is stopped, generally there is a gradual or stepwise progression in energy cacochimia. As a result, the cells lose their functions with the elapse of time, and the cells are soon organically broken. Thus, the cerebral cells cannot effect their normal functions. Therefore, a mechanism to adjust cerebral bloodstreams in the cerebral blood vessels themselves has been fully developed to stably supply the energy sources to the cerebral tissues and to maintain the outer environments of cerebral nerve cells.
Various cerebral circulation ameliorating agents (or circulating improvers), cerebral vasodilators, and cerebral excitometabolites have been heretofore used for the medical treatment of cerebral blood vessel disorders. However, although these medicines are effective for ameliorating subjective symptoms, no substantial amelioration in neural symptoms and mental symptoms are observed. Of these medicines, it is reported in, for example, Japanese Unexamined Patent Publication (i.e., Kokai Nos. 58-110547 and 55-17329 and Japanese Examined Patent Publication (Kokoku) No. 41-732 that 4-amino butyric acid derivatives are considered to be effective for curing dementia and amnesia. Furthermore, it is proposed in, for example, Japanese Unexamined Patent Publication (Kokai) Nos. 50-24276 and 52-19672 that diaryl butyric acid derivatives are useful as medicines for treatment of central nervous system disorders.
In addition, although various medical studies have been made into the amelioration and cure of senile dementia, there still remain many problems to be solved because of the presence of various psychogender functional symptoms. For this reason, families and other persons must take great care when nursing these patients, which need becomes a serious social problem.